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Error: Commands out of sync; you can't run this command now

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Join Date: May 2007

Posts: 459

Reputation: Atli is on a distinguished road

Solved Threads: 57

Atli

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Posting Pro in Training

#11

Nov 2nd, 2009

I'm glad you got it working

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Originally Posted by sam023

but in coding i made two config file.. one with mysql other with msqli..!!!

That's actually pretty bad. Really bad, to be honest :/
You've got two open connections now, which is just a waste.

I strongly recommend you try to use the function I posted in my first post, or at least use the mysqli functions to do both queries, like:

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 php Syntax (Toggle Plain Text) 
// Call the first procedure
$result1 = mysqli_query($dbLink, "CALL `TestProc`(1);");
 
// Do something with the result
// etc...
 
// Free the results up for the next query
mysqli_free_result($result1);
while(mysqli_more_results($dbLink) && mysqli_next_result($dbLink)) {
    $dummyResult = mysqli_use_result($dbLink);
    if($dummyResult instanceof mysqli_result) {
        mysqli_free_result($dbLink);
    }
}
 
// Call the next procedure
$result2 = mysqli_query($dbLink, "CALL `TestProc`(2);");
// etc...
// Call the first procedure
$result1 = mysqli_query($dbLink, "CALL `TestProc`(1);");

// Do something with the result
// etc...

// Free the results up for the next query
mysqli_free_result($result1);
while(mysqli_more_results($dbLink) && mysqli_next_result($dbLink)) {
    $dummyResult = mysqli_use_result($dbLink);
    if($dummyResult instanceof mysqli_result) {
        mysqli_free_result($dbLink);
    }
}

// Call the next procedure
$result2 = mysqli_query($dbLink, "CALL `TestProc`(2);");
// etc...

This way you can drop the old mysql connection but still do both procedures.

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Originally Posted by sam023

can u give link to basic tutorial of mysqli..?

There is hardly any need for a tutorial like that. The mysqli extension was designed to replace the old mysql extension very easily, and almost everything else you need to know can be found in the manual. Every function is documented there, with loads of examples and user submitted comments.

But to replace the old mysql functions, there are only two things you really need to know:

#1 The way you connect to a database is different:

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$mysqli = new mysqli("localhost", "my_user", "my_password", "db_name");
 
/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
$mysqli = new mysqli("localhost", "my_user", "my_password", "db_name");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

#2 You need to pass the database object (the $mysqli in the previous example) into the query function as the first parameter:

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mysqli_query($mysqli, "SELECT something");
mysqli_query($mysqli, "SELECT something");

Knowing those two things, you should be able to code almost exactly as you would have using the old mysql extension. The function names are almost identical, except for the added "i" ;-)

There are of course a few new features that you can use, now that you have upgraded.
Like:

OOP. The mysqli object is in fact an object, which allows for OOP style syntax. Just pick any mysqli function in the manual and check out the OOP examples and see the difference.
Prepared statements (See the examples). Eliminates the risk of SQL Injection, which is one of the biggest security risks for PHP applications.
Improved speed! Nuff said.
Execute multiple queries at once, via the mysqli::multi_query method.
Transactions. Gives you the ability to execute a series of queries, but only committing the changes to the database when you are ready, or rollback the changes in case of a problem.

There is probably more that I'm not remembering right now :-]